The present invention refers to a coaxial cable fitting, and in particular to a coaxial cable fitting of the type in which a metal bush receives a cable end of the coaxial cable and makes electric contact with the cable outer conductor having a section bent outwardly about an annular surface of a contact clamp which is placed over the cable end and forced by a screw element against the metal bush so as to press the outer conductor against a radial shoulder of the metal bush.
Coaxial cable fittings of this type are generally known and are suitable for providing a tension-proof and, if necessary, a sealed connection of a coaxial cable with a rigid connector such as a plug, a jack or a coupling. Generally, the coaxial cable fitting is of stuffing box-like design in which a screw element such as a hollow screw plug or a coupling ring and a radially elastic contact clamp cooperate with each other to attain the axially oriented contact pressure and a sufficient mechanically tight connection between the cable outer conductor or the cable sheath and the metal bush e.g. the plug. The connection of the inner conductor can be accomplished in various ways which are, however, independent of the type of the outer conductor connection and thus of no relevance with regard to the present invention.
In conventional coaxial cable fittings, the metal bush is provided at its part receiving the cable end with a hollow-cylindrical bore in which the contact clamp is centered and guided with its complementary cylindrical outer circumferential surface. Since the screw element and the contact clamp are frictionally engaged, the contact clamp often rotates during tightening of the screw element leading to a twisting of the cable because the contact clamp is also frictionally engaged with the outer conductor or the cable sheath. A twisting of the cable is, however, disadvantageous not only for mechanical reasons and electrical reasons but also because it leads to a torsional strain of the cable inner conductor since the latter is generally non-rotatably connected with the inner conductor contact element of the cable fitting which in turn is non-rotatably mounted. Evidently, this torsion may result in premature rupturing especially of coaxial cables with sensitive inner conductor.